Linux distributor Xandros is licensing messaging protocols from Microsoft as part of an expansion of the partnership the two companies forged in June.

Xandros, which offers desktop and server versions of Linux, is acquiring the specification and licenses for Exchange ActiveSync and Outlook-Exchange Transport Protocol so its Scalix Mail Servers can better interoperate with Microsoft clients that now primarily interact with Microsoft's Exchange Server messaging infrastructure.

Microsoft and Xandros first announced a pact to make their products more interoperable in June during Microsoft's annual TechEd conference. Microsoft also agreed not to sue Xandros users for patent-infringement. Microsoft claimed earlier this year that Linux violates more than 230 patents it holds.

Microsoft has been collecting Linux vendors such as Novell and Xandros as alliance partners in what some see as an effort to appear more friendly to the open-source OS, which is a strong competitor to its Windows Server OS. For their part, Linux vendors want to protect their customers from any potential patent-infringement claims from Microsoft. And Xandros, being one of the less successful Linux vendors, gains a competitive advantage by teaming up with the software giant.

ActiveSync enables synchronization of Windows Mobile and Windows CE devices to connect with server-side information from Exchange. Xandros will develop a server-side implementation of Exchange ActiveSync so Xandros' Scalix Mail Servers can synchronize data over wireless networks directly with mobile clients that use ActiveSync, said Florian von Kurnatowski, director of program management for Scalix at Xandros.

Currently, ActiveSync-enabled devices can interact directly with Scalix Mail Servers if third-party software is installed locally on the client. Xandros' ActiveSync implementation will eliminate the need for that software, which can be cumbersome and is just an added expense for end users, von Kurnatowski said.

Microsoft's Outlook-Exchange Transport Protocol allows desktop clients such as Microsoft Outlook running on the Windows OS to communicate directly with Exchange Server.

He added that creating an ActiveSync implementation is more important to Xandros than creating software using the Outlook-Exchange protocol, because of the complexity of getting users to install third-party software on mobile devices versus the relative ease of using Xandros' own Scalix Connect software on clients. "It's less of a priority than ActiveSync," von Kurnatowski said.

Xandros should produce the first results from its implementation of the protocols in six to 12 months, he said.